BE ON THE LOOKOUT FOR INSOMNIA'S SECRET COUSIN: UNTREATED OSA

You can't sleep at night. You've taken every pill, and none of them work. You still get up several hours a night and have trouble falling back asleep. But you haven't had a sleep study yet.

Maybe it's time you had a sleep study.

It has been common practice to separate the majority of insomniacs from other sleep disordered patients and place them in the therapy/pharmacology track to treat their problems with sleeplessness. Overnight sleep studies are expensive and it has been thought that such a diagnostic test would not be the first course of action for someone who seemed to only suffer from insomnia.

However, a recent study published by the Mayo Clinic, led by physician Dr. Barry Krakow, discovered that many people being treated for insomnia, who had failed all pharmacological treatments, actually suffer from undiagnosed and untreated obstructive sleep apnea.

“We are used to seeing insomnia as a psychological condition, but in these drug-failure cases nearly all patients also suffered from a physical condition, obstructive sleep apnea,” said Dr. Krakow.

The study, published last September, observed over 1200 patients with chronic insomnia, 900 of which were using (and failing at) some kind of sleep aid. Those with prescription sleep aids seemed to suffer the most, interestingly, reporting more delayed sleep onset, more wakeful periods during the night and the lowest sleep efficiency, all of which are consistent with severe insomnia. Assessing over 900 of these patients via a sleep study using the most advanced respiratory technology revealed a mind-blowing 91 percent of them had a confirmed diagnosis of moderate to severe obstructive sleep apnea.

This is a huge finding, as many patients may now be prompted to have an overnight sleep study to determine the likelihood they have unresolved apnea, something not commonly done before with patients assumed to only have insomnia.

Dr. Krakow was asked, in a CHEST Physician interview, what made him think to study breathing patterns in insomnia patients who were not complaining of traditional OSA symptoms.

"We asked insomnia patients to tell us why they wake up and found that the causes they attribute to their awakenings are very different from what we see in the sleep lab. Fifty percent say it’s mental and 50 percent say it’s physical," he said. "They’ll also point to things after the fact, such as 'I woke up because my mind is racing' and then realize that the racing thoughts really emerged after the awakening. In the lab, however, breathing events were the most common cause of their awakenings."

It makes sense. Sleep apnea can perpetuate insomnia as it causes sleep fragmentation, which disrupts the sleep cycle with frequent awakenings. Patients awaken upon having apneic episodes but think they have insomnia or need to use the restroom. Frequently rising to urinate may also be a hallmark of undiagnosed sleep apnea; when the body undergoes an apneic episode, and the patient awakens gasping for air (which they may or may not be consciously aware of), it sets off a chain of stress responses in the body which leads to signals of awakening, which prompt the body to empty the bladder, whether it is full or not.

Senior research investigator Victor Ulibarri also pointed out that “remarkably, greater than 70 percent of this patient population reported sleep breathing symptoms like snoring or gasping during sleep and suffered from insomnia for an average of a decade, yet none of these patients had previously been evaluated or referred for sleep testing.”

This generates the concern that primary care physicians, who are the chief referring doctors for sleep studies, may not be asking enough of or the right questions during a general healthcare visit to discern whether the origin of a patient's potential insomnia is psychological or possibly physiological. It can also be hard to determine when sleep medications are failing, which can lead to significant problems with evaluating sleep problems on a timely basis when they are initially only linked to insomnia.

Dr. Krakow points out that “doctors may be confused or challenged in sorting out when patients need medication or an evaluation at a sleep medical center.”

Senior research investigator Natalia D. McIver warns that drugs are not always going to be the way a sleep problem is fixed. "Insomnia patients perplexed by their sleeplessness may steer doctors toward quick fixes with pills. But, when we show patients the importance of sleep breathing, they are eager to attempt effective sleep apnea treatments.”

And they should be. Many medications used for sleep onset for insomniacs depress the respiratory system; if someone with a sleep-breathing disorder takes these drugs, they may in fact make their condition worse.

Ultimately, the research points to more expedited referrals of insomnia patients for sleep testing to rule out sleep breathing disorders so as to identify which patients truly benefit from therapies for apnea versus those who may do better on a sleep medication.